Glass and the method of making it



United States Pate 2,920,972 GLASS AND THE METHOD OF MAKING IT Claims priority, application France June 11, 1954 23 Claims. (Cl. 10647) This invention relates to the manufacture of novel glasses, to novel methods of making them, to novel compositions of matter used in their manufacture, and to novel uses therefor. Among the novel uses of the novel glass are lubrication in metal working and the fertilization of land. The invention will be most particularly described in its application to metal drawing, but that description is not to be taken as a limitation on the generality of what is elsewhere stated and claimed herein;

It is known that the drawing of non-ferrous metals and alloys presents gave difiiculties'arising principally from the high friction. which develops between the ingot and the working parts of the press. This high friction raises the temperature locally on the surface of the ingot and produces flaws in the'surface of the drawn metal. Furthermore, because of the friction the core of the piece is drawn quicker than the parts in contact with the tools of the press and produces local high tensions and a heterogeneous structure characterized by large grains in the surface of the drawn metal, which appeara't the time of latertherinal treatments. one particular fault is the production of an axial recess in the end of the drawn piece which may extend for of the length of the drawn-piece.

surface fiawsis to reduce the speed of drawing to no more than 3 meters per minute, in order to allow the heat produced by friction to be dissipated. In addition to reducing'the productivity of the press that method fails he-usual method of eliminating the production ofthe to eliminate the formation of extra large, gross grains in the circumference or the axial recess.

It has also been proposed, for drawing at elevated temperature those metals which are hard to draw, to interpose some material that will melt partially or wholly at the temperature of drawing while remaining viscous after melting, such as glass, oxides, salts or slag, between the drawn piece and the tools of the press, in particular the die. None of the proposed lubricants has yet overcome the problems relating to the drawing of non ferrous metals and alloys in a wholly satisfactory manner. It is to the solution of such problems that a major part of this invention is addressed. 7

This invention comprises a discovery that the glass compositions hereinafter described maintain a lubricating viscosity in the temperature range from about 300 C. to about 550 C. and may be used as lubricants for drawing metals and alloys having low melting points, especially aluminum and its alloys, for which the temperature reached by the lubricant during working or drawing falls in this range. The fritting temperature of the novel glasses described herein is between about 280 C. and 440 c.

Great advantages are acquired by using the glasses described and claimed herein in metal drawing. The speed of drawing may be increased to the order of 15 to 50 m. per minute, in particular in the drawing of aluminum and its alloys. The gross peripheral grains are not produced after subsequent thermal treatment. The axial recess is eliminated. An especial advantage is that .theseglasses can be removed from the surface to increase its chemical and weather resistance.

ice

of the drawn body without the use of dilute HF, using, for example, only dilute HNO and in the case of the class of glasses low in or lacking alumina, merely water.

Another commercial use of these glasses is as carriers for fertilizer oligo-elements. The commercial fertilizers ofthe present market liberate their fertilizing elements in bulk at the first good rain, which is not as desirable as would be a slower release extending over a longer period of time. By incorporating the oligo-elements such as oxides of manganese, iron, zinc, copper, molybdenum and boric anhydride in the following glasses there are produced fertilizers which are decomposed slowly by rain and other agents, liberating phosphoric acid from the glass itself as well as the oligo elements that have been introduced into it. This insures a more uniform and gradual supply of such elements than is furnished by present methods.

In addition to the foregoing novel methods to which this invention is adapted, another, depending from a certain degree of solubility of these glasses in water, is made available. Certain catalysts used in the gas industry must be agglomerated before being used by materials practically free of silica. Sodium silicate is much employed in related agglomerations but cannot be used in cases where silica may not be used. The present glasses which also have a certain solubility in water, but which are substantially silica free, are useful in carrying out such agglomerations.

These new glasses are less acid than phosphoric acid or boric acid, and are less basic than diammonium phos- .there is no B 0 although B 0 can be substituted for P 0 up to about 5% of the weight of the glass in order It will thus be seen that the sum of P 0 and B 0 has a minimum of about 50 percent.

They may or may not contain A1 0 but if it is present the total amount of P 0 B 0 and Alumina should not materially exceed 66%. Thus the P 0 may attain about 66% when B 0 and A1 0 are lacking. The A1 0 ranges from O to a maximum of 16 percent.

They contain 9-13% of the group composed of PbO, BaO, and the other alkaline-earth oxides, PbO and/or BaO always being in preponderant amount. In other words, PbO and/or BaO are preferred but a small percentage of them may be replaced by at least one other alkaline earth oxide, e.g. lime or magnesia.

They contain 24-35% of Na O, or an equivalent molecular amount of at least one other alkali oxide, for example, potassium oxide or lithium oxide. This enables one to vary the surface tension of the product, its fusibility, its alterability and its tendency to devitrify. If it is desired to improve resistance to chemical agents and weather, a small amount of the alkali metal oxide, eg. 5% calculated as Na O, may be replaced by ZnO. The ratio of the total weight of alkali metal oxide (calculated as Na O) and ZnO to the total weight of PhD and BaO and other alkaline earth oxide is from 3 minimum to maximum.

The lead oxide may be kept below 5% if it isnecessary or desired.

The following examples illustrate various phases of the invention.

Example 1 A mixture of 109.5 parts by weight of hydrated trisodium phosphate, 64 parts of monoammonium phosphate, 5.15 parts of red lead oxide, and 10.7 parts of barium carbonate are melted at about 900 C. in a silica crucible and pouredon'a table, producing a slightly opalescent glass without any tendency to devitrify. Its composition by weight analysis is:

Percent P 5 7 PhD 4.45 BaO 7.45 Na O 3 1.10

The composition of the vitrifiable mixture employed in making the disc, and the analysis of the finished glass,

4 Poured on a table it produces a clean non-opalescent glass of the following analysis by weight:

Percent P 0 48.8 B 0 5 A1 0 6.5 PbO 4.5 BaO 5.4 ZnO 4 Na O 25 .8

The composition of the vitrifiable mixture, and the analysis of the finished glass are given in the following table:

Composition of the Vitrifiable Material Chemical Composition of the Corresponding Glass P B10; A120: PbO BaO ZnO N810 81.3 parts by weight of hydrated trisodium phosphate containing 22.1% by weight of P10 and 31.8% by weight of Nero.

61.7 parts by weight of diammonium phosphate containing 50.0% by weight of P O a r 8.9 parts by weight of boric acid (B(OH)a) 9.9 parts by weight of hydrated alumina Al (OH): 4.6 parts by weight, red lead oxide (Pb304) 6.9 parts by weight of barium carbonate (CO Ba)- 4.0 parts by weight of zinc oxide (ZnO) Total, parts by weight Total, percentage by weight are set out more fully in the following table:

Chemical Composition of the Composition of the Vitrifiable Corresponding Glass Material Pros A110; PbO BaO N820 99.0 parts by weight or hydrated trisodium phosphate containing 22.1% by weight of P20 and 31.8% by weight of N arO 61.2 parts by weight of diammonium phosphate containing 50.0% by weight of P10 6.1 parts by wei ht of hydrated alumina Al(OH 4.6 parts by weight red lead oxide (Pbiol)- 9.65 parts by weight of barium carbonate (00 132;)

Total, parts by weight Total, percentage by weight.

The glass is pulverized by being ground, and it is then passed to a 55 screen, which has the openings between the wires measuring from .299 to .331 mm. on a side. The glass which passes through the 55 screen is then passed to a 100 screen, which has the openings between the wires lying between .152 and .168 mm. on a side. The material which remains upon the 100 screen is that employed in making the disc. A stainless steel mold having a cavity 145 mm. in diameter and 3 mm. in depth was filled with such material. The mold and its contents were introduced into an electric resistance furnace, where it was held at a temperature of 285 C. for minutes. Atthe end of that time the mold was withdrawn from the furnace. The product thus treated in the mold was a disc made up of fritted grains, that is, the grains were bonded to each other but remaine distinct.

Example 2 The following batch is vitrified as in Example 1 but at 920 0.:

Parts by weight After pulverizing to .l5-.30 mm. a disk 145 x 3 mm. was made and molded as in Example 1. Said disc was sintered at 440 C. in 25 minutes.

Example 3 g It being desired to extrude an aluminum alloy containing Cu 1.6 parts by weight,'Mn 0.2, Mg 2.5, Cr 0.3, Zn 5.6, a disk was made with a granulated glass containing by weight:

1 Percent P 0 52.5 M 0 4 PhD 4.5 BaO 7.5 Na O 31.5

A more complete analysis of the materials employed in making the raw batch, as well as the manner of calculation of the above analysis, are set out in the table below:

Chemical Composition of the Corresponding Glass Composition of the Vitriflable Material P|0| PbO BaO NarO 109.5 parts by weight of hydrated trisodium phosphate containing 22.1% by weight of P105 and 31.8% by weight of N820 24. 2 34. 64.0 parts by weight of monoammonium phosphate containing 61.7% by weight 01 PzOr 39.5 5.15 parts by weight red lead oxide (PbaOr) 5.0 10.70 parts by weight of barium carbonate Total, parts by weight 63. 7 5.0 8.3 34.85 Total, percentage by weight 57 4. 45 7. 45 31.1

After pulverizing to .15-30 mm. the disc was made and molded as in Example 1. Said disc was fritted at 370 C. in 25 minutes. The speed of drawing the alloy through the die, the plate made by fritting having been placed between die and ingot before the drawing, was 18 meters per minute. The product had no axial recess at the end and later thermal treatments showed no peripheral gross grains.

The alumina confers on glasses in accordance with the invention a hygroscopicity which decreases as the proportion of alumina increases. The alumina raises the temperature of fritting and improves resistance to chemicals. and weather.

The lead oxide and baryta increase the fusibility. The

alkali lowers the fritting temperature but we have found that an increase in alkali beyond the range indicated may produce products that tend to devitrify on cooling and even to produce pro-ductsthat vitrify with difiiculty.

ing constituents within the following boundaries:

P205 45% minimum to 66% maximum. B203 minimum to maximum.

P205+B20s 50% minimum to 66% maximum.

0% minimumto 16% maximum.

P 05+B20s+A12Os 50% minimum to 66% maximum.

0% minimum to 13% maximum. BaO 0% minimum to 13% maximum.

PbO BaO other alkaline earth oxide Alkali metal oxide (calculated as NazO) ZnO Alkali metal oxide (calcu lated as N-a20) +Zn0--- Alkali metal oxide (calculated as NaeO) ZnO/ Pb0+BaO+other alkaline earth oxides 2/1 minimum to 3.5/1 maximum. PbO+BaO are preponderant over other alkaline earth oxides, said other alkaline earth oxides may be 0.

2. Glass having the following composition by weight analysis: 5066% of the group consisting of P 0 A1 0 and B 0 the total of P 0 and B 0 being at least 50% of the composition, the B 0 preferably not exceeding about 5%, 9-13% of the group consisting of PbO, BaO, and the other alkaline earth oxides, the oxide of the group other than PhD and BaO being no greater than 5%, 2435% of the group consisting of the alkali oxides calculated as Na O and ZnO, the ZnO being no greater than 5%, the ratio of total weight of alkali oxide calculated as Na O and ZnO to the total weight of lead oxide and BaO and other alkaline earth oxide being between about 2 and 3.5.

3. Glass having the following composition by weight analysis: 50 to 66% of phosphorus anhydride (P 0 and boric anhydride (B 0 and alumina (A1 0 phosphorus anhydride (P 0 being present by at least 45%, the total amount of P 0 and boric anhydride (B 0 being at least 50%, and B 0 being at most 5 9 to 13% of at least one of PhD and BaO, alkaline metal oxide equivalent to 24 to 35% of Na O, the ratio of weight of alkali metal oxide calculated as Na O to the total weight of PhD and BaO being between 2 and 3.5.

4. Glass having the following composition by weight analysis: 50 to 66% of phosphorus anhydride (P 0 and boric anhydride (B 0 and alumina (A1 0 phosphorus anhydride (P 0 being present by at least 45%, the total amount of P 0 and boric anhydride (B 0 being at least 50%, and B 0 being at most 5%, 9 to 13% of BaO, alkali metal oxide equivalent to 24 to 35% of Na O, the ratio of weight of alkali metal oxide calcu lated as Na O to the weight of H210 being between 2 and 3.5

5. Glass having the following composition by weight analysis: 50 to 66% of phosphorus anhydride (P 0 and boric anhydride (B 0 andalumina (Al O phosphorus anhydride (P 0 being present by at least 45%, the total amount of P 0 and boric anhydride (B 0 being at least 5 0%, and B 0 being at most 5%, 9 to 13% of PbO, alkali metal oxide equivalent to 24 to 35 of N-a O, the ratio of the weight of alkali metal oxide calculated as Na O to the weight of PhD being between 2 and 3.5.

6. Glass having the following composition by weight analysis: 50 to 66% of phosphorus anhydride (P 0 9% minimum to 13% maximum.

19% minimum to 35% maximum. 0% minimum to 5 maximum.

2 l% minimum to 35% maximum.

, 6 and alumina (A1 0 P O --being present by at least 50%, 9 to 13% of BaO and PbO,'alkali metal oxide equivalent to' 24 to 35% of Na O, the ratio of the weight of alkali metal oxide calculated as Na O to the total weight of BaO ,and PbO being between 2 and 3.5.

7. Glass having the following composition by weight analysis: SO-to 66% of phosphorus anhydride (P 0 and alumina (A1 0 P 0 being present by at least 50%, 9 to 13% of PbO, alkali metal oxide equivalent to 24 to 35% of Na O, the ratio of the weight of alkali metal oxide calculated as Na O to the weight of PbO being between 2 and 3.5.

8. Glass having the following composition by weight analysis: 50 to 66% of phosphorus anhydride (P 0 and alumina (A1 0 P 0 being present by at least 50%, 9 to 13% of BaO, alkali metal oxide equivalent to 24 to 35 of Na O, the ratio of the weight of alkali metal oxide calculated as Na O to the weight of BaO being between 2 and 3.5.

9. Glass having the following composition by weight analysis: 50 to 66% of phosphorus anhydride (P 0 and boric anhydride (B 0 and alumina (Al O phosphorus anhydride (P 05) being present by at least 45 the total amount of P 0 and boric anhydride (B 0 being at least 50%, and B 0 being at most 5%, 9 to 13% of PbO, and at leastone alkali oxide corresponding in molecular proportions to 24 to 35% by weight of sodium oxide, the ratio of the weight of the alkali oxide, calculated as Na o to the weight of PbO being between 2 and 3.5.

10. Glass having the following composition by weight analysis: 50 to 66% of phosphorus anhydride (P 0 and boric anhydride (B 0 and alumina (A1 0 phosphorus anhydride (P 0 being present by at least 45 the total amount of P 0 and boric anhydride (B 0 being at least 50%, and B 0 being at most 5%, 9 to 13% of BaO, and at least one alkali oxide corresponding in molecular proportions to 24-35% by weight of sodium oxide, the ratio of the weight of the alkali oxide calculated as Na O to the weight of BaO being between 2 and 3.5. a

11. Glass having the following composition by weight analysis: 50 to 66% of phosphorus anhydride (P 0 and boric anhydride (B 0 and alumina (A1 0 phosphorus anhydride (P 0 being present by at least 45 the total amount of P 0 and boric anhydride (B 0 being at least 50%, and B 0 being at most 5%, 9 to 13% of BaO and PbO, and at least one alkali oxide corresponding in molecular proportions to 24-35% by Weight of sodium oxide, the ratio of the weight of the alkali oxide calculated as Na O to the total weight of B210 and P being between 2 and 3.5.

12. A glass according to claim 11 in which a relatively small part of the percentage of BaO and PhD is replaced by calcium oxide, and the ratio of the weight of the alkali oxide, calculated as Na O, to the total weight of BaO and PbO and CaO being between 2 and 3.5.

13. A glass according to claim 9 in which a relatively small part of the percentage of PhD is replaced by calcium oxide, and the ratio of the weight of the alkali oxide, calculated as Na O, to the total weight of PbO and CaO being between 2 and 3.5.

14. A glass according to claim 10 in which a relatively small part of the percentage of BaO is replaced by C210, and the ratio of the weight of the alkali oxide, calculated as Na O, to the total weight of BaO and C210 being between 2 and 3.5.

15. A glass according to claim 11 in which a relatively small part of the percentage of BaO and PbO is replaced by magnesium oxide, and the ratio of weight of alkali oxide, calculated as Na O, to the total weight of BaO and PbO and MgO being between 2 and 3.5.

16. A glass according to claim 9 in which a relatively small part of the percentage of PhD is replaced by magnesium oxide, and the ratio of the weight of alkali oxide,

aaaaa m calculated as Na O, to the total weight of PhD and MgO being between 2 and 3.5. I

I 17. A glass according to claim 10 in which a relatively small part of the percentage of BaO is replaced by magnesium oxide, and the ratio of the weight of alkali oxide, calculated as Na O, to the total weight of BaO and MgO being between 2 and 3.5. i

18. A glass according to claim 11 in which a small amount of alkali oxide calculated as Na O,- at most 5%, is replaced by ZnO, and the ratio of the total weight of alkali oxide, calculated as Na O, and ZnO to the total weight of BaO and PbO being between 2-and 3.5.

19. A glass according to claim 9 in which a small amount of alkali oxide calculated as Na O, at most 5%, is replaced by ZnO, and the ratio of the total weight of alkali oxide, calculated as Na O, and ZnO to the weight of PbO beingbetween 2 and 3.5.

20. A glass according to claim 10 in which a small amount of alkali oxidecalculated as Na O, at most 5 is replaced by ZnO, and the ratio of the total weight of alkali oxide, calculated as Na O, and ZnO to the weight of BaO being between 2 and 3.5.

21. Glass having a composition by weight percentage equivalent to:

Na O 31. 1

8 22; Glass having a composition by weight percentage equivalent to:

0 7 48.8 5 13,0, I I 5.0 A1203 v PbO 4.5

BaO 5,4 ZnO' I 4.0 10 Na O I 25.8

23. Glass having a composition by weight percentage equivalent to:

References Cited in the file of this patent UNITED STATES PATENTS Slayter et a1 Mar. 12, 1940 

1. GLASS CONTAINING BY WEIGHT PERCENTAGE THE FOLLOWING CONSTITUENTS WITHIN THE FOLLOWING BOUNDARIES: 